/*
 * SPDX-License-Identifier: Apache-2.0
 *
 * The OpenSearch Contributors require contributions made to
 * this file be licensed under the Apache-2.0 license or a
 * compatible open source license.
 */

/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch licenses this file to you under
 * the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
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/*
 * Modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

package org.opensearch.script;

import org.opensearch.cluster.DiffableUtils;
import org.opensearch.core.common.bytes.BytesArray;
import org.opensearch.core.common.bytes.BytesReference;
import org.opensearch.core.common.io.stream.Writeable;
import org.opensearch.core.xcontent.DeprecationHandler;
import org.opensearch.core.xcontent.MediaType;
import org.opensearch.core.xcontent.NamedXContentRegistry;
import org.opensearch.core.xcontent.XContentBuilder;
import org.opensearch.common.xcontent.XContentFactory;
import org.opensearch.core.xcontent.XContentParser;
import org.opensearch.common.xcontent.XContentType;
import org.opensearch.test.AbstractSerializingTestCase;

import java.io.IOException;
import java.io.UncheckedIOException;
import java.util.Collections;

public class ScriptMetadataTests extends AbstractSerializingTestCase<ScriptMetadata> {

    public void testFromXContentLoading() throws Exception {
        // failure to load to old namespace scripts with the same id but different langs
        XContentBuilder builder = XContentFactory.jsonBuilder();
        builder.startObject().field("lang0#id0", "script0").field("lang1#id0", "script1").endObject();
        XContentParser parser0 = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        expectThrows(IllegalArgumentException.class, () -> ScriptMetadata.fromXContent(parser0));

        // failure to load a new namespace script and old namespace script with the same id but different langs
        builder = XContentFactory.jsonBuilder();
        builder.startObject()
            .field("lang0#id0", "script0")
            .startObject("id0")
            .field("lang", "lang1")
            .field("source", "script1")
            .endObject()
            .endObject();
        XContentParser parser1 = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        expectThrows(IllegalArgumentException.class, () -> ScriptMetadata.fromXContent(parser1));

        // failure to load a new namespace script and old namespace script with the same id but different langs with additional scripts
        builder = XContentFactory.jsonBuilder();
        builder.startObject()
            .field("lang0#id0", "script0")
            .field("lang0#id1", "script1")
            .startObject("id1")
            .field("lang", "lang0")
            .field("source", "script0")
            .endObject()
            .startObject("id0")
            .field("lang", "lang1")
            .field("source", "script1")
            .endObject()
            .endObject();
        XContentParser parser2 = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        expectThrows(IllegalArgumentException.class, () -> ScriptMetadata.fromXContent(parser2));

        // okay to load the same script from the new and old namespace if the lang is the same
        builder = XContentFactory.jsonBuilder();
        builder.startObject()
            .field("lang0#id0", "script0")
            .startObject("id0")
            .field("lang", "lang0")
            .field("source", "script1")
            .endObject()
            .endObject();
        XContentParser parser3 = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        ScriptMetadata.fromXContent(parser3);
    }

    public void testGetScript() throws Exception {
        ScriptMetadata.Builder builder = new ScriptMetadata.Builder(null);

        XContentBuilder sourceBuilder = XContentFactory.jsonBuilder();
        sourceBuilder.startObject()
            .startObject("script")
            .field("lang", "_lang")
            .startObject("source")
            .field("field", "value")
            .endObject()
            .endObject()
            .endObject();
        MediaType mediaType = sourceBuilder.contentType();
        builder.storeScript("source_template", StoredScriptSource.parse(BytesReference.bytes(sourceBuilder), mediaType));

        sourceBuilder = XContentFactory.jsonBuilder();
        mediaType = sourceBuilder.contentType();
        sourceBuilder.startObject().startObject("script").field("lang", "_lang").field("source", "_source").endObject().endObject();
        builder.storeScript("script", StoredScriptSource.parse(BytesReference.bytes(sourceBuilder), mediaType));

        ScriptMetadata scriptMetadata = builder.build();
        assertEquals("_source", scriptMetadata.getStoredScript("script").getSource());
        assertEquals("{\"field\":\"value\"}", scriptMetadata.getStoredScript("source_template").getSource());
    }

    public void testDiff() throws Exception {
        ScriptMetadata.Builder builder = new ScriptMetadata.Builder(null);
        builder.storeScript(
            "1",
            StoredScriptSource.parse(new BytesArray("{\"script\":{\"lang\":\"mustache\",\"source\":{\"foo\":\"abc\"}}}"), XContentType.JSON)
        );
        builder.storeScript(
            "2",
            StoredScriptSource.parse(new BytesArray("{\"script\":{\"lang\":\"mustache\",\"source\":{\"foo\":\"def\"}}}"), XContentType.JSON)
        );
        builder.storeScript(
            "3",
            StoredScriptSource.parse(new BytesArray("{\"script\":{\"lang\":\"mustache\",\"source\":{\"foo\":\"ghi\"}}}"), XContentType.JSON)
        );
        ScriptMetadata scriptMetadata1 = builder.build();

        builder = new ScriptMetadata.Builder(scriptMetadata1);
        builder.storeScript(
            "2",
            StoredScriptSource.parse(
                new BytesArray("{\"script\":{\"lang\":\"mustache\",\"source\":{\"foo\":\"changed\"}}}"),
                XContentType.JSON
            )
        );
        builder.deleteScript("3");
        builder.storeScript(
            "4",
            StoredScriptSource.parse(new BytesArray("{\"script\":{\"lang\":\"mustache\",\"source\":{\"foo\":\"jkl\"}}}"), XContentType.JSON)
        );
        ScriptMetadata scriptMetadata2 = builder.build();

        ScriptMetadata.ScriptMetadataDiff diff = (ScriptMetadata.ScriptMetadataDiff) scriptMetadata2.diff(scriptMetadata1);
        assertEquals(1, ((DiffableUtils.MapDiff) diff.pipelines).getDeletes().size());
        assertEquals("3", ((DiffableUtils.MapDiff) diff.pipelines).getDeletes().get(0));
        assertEquals(1, ((DiffableUtils.MapDiff) diff.pipelines).getDiffs().size());
        assertNotNull(((DiffableUtils.MapDiff) diff.pipelines).getDiffs().get("2"));
        assertEquals(1, ((DiffableUtils.MapDiff) diff.pipelines).getUpserts().size());
        assertNotNull(((DiffableUtils.MapDiff) diff.pipelines).getUpserts().get("4"));

        ScriptMetadata result = (ScriptMetadata) diff.apply(scriptMetadata1);
        assertEquals("{\"foo\":\"abc\"}", result.getStoredScript("1").getSource());
        assertEquals("{\"foo\":\"changed\"}", result.getStoredScript("2").getSource());
        assertEquals("{\"foo\":\"jkl\"}", result.getStoredScript("4").getSource());
    }

    public void testBuilder() {
        ScriptMetadata.Builder builder = new ScriptMetadata.Builder(null);
        builder.storeScript(
            "_id",
            StoredScriptSource.parse(new BytesArray("{\"script\": {\"lang\": \"painless\", \"source\": \"1 + 1\"} }"), XContentType.JSON)
        );

        ScriptMetadata result = builder.build();
        assertEquals("1 + 1", result.getStoredScript("_id").getSource());
    }

    public void testLoadEmptyScripts() throws IOException {
        XContentBuilder builder = XContentFactory.jsonBuilder();
        builder.startObject().field("mustache#empty", "").endObject();
        XContentParser parser = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        ScriptMetadata.fromXContent(parser);
        assertWarnings("empty templates should no longer be used");

        builder = XContentFactory.jsonBuilder();
        builder.startObject().field("lang#empty", "").endObject();
        parser = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        ScriptMetadata.fromXContent(parser);
        assertWarnings("empty scripts should no longer be used");

        builder = XContentFactory.jsonBuilder();
        builder.startObject().startObject("script").field("lang", "lang").field("source", "").endObject().endObject();
        parser = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        ScriptMetadata.fromXContent(parser);
        assertNoDeprecationWarnings();

        builder = XContentFactory.jsonBuilder();
        builder.startObject().startObject("script").field("lang", "mustache").field("source", "").endObject().endObject();
        parser = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        ScriptMetadata.fromXContent(parser);
        assertNoDeprecationWarnings();
    }

    public void testOldStyleDropped() throws IOException {
        XContentBuilder builder = XContentBuilder.builder(XContentType.JSON.xContent());

        builder.startObject();
        {
            builder.startObject("painless#test");
            {
                builder.field("lang", "painless");
                builder.field("source", "code");
            }
            builder.endObject();
            builder.startObject("lang#test");
            {
                builder.field("lang", "test");
                builder.field("source", "code");
            }
            builder.endObject();
            builder.startObject("test");
            {
                builder.field("lang", "painless");
                builder.field("source", "code");
            }
            builder.endObject();
        }
        builder.endObject();

        XContentParser parser = XContentType.JSON.xContent()
            .createParser(
                NamedXContentRegistry.EMPTY,
                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                BytesReference.bytes(builder).streamInput()
            );
        ScriptMetadata smd = ScriptMetadata.fromXContent(parser);
        assertNull(smd.getStoredScript("painless#test"));
        assertNull(smd.getStoredScript("lang#test"));
        assertEquals(new StoredScriptSource("painless", "code", Collections.emptyMap()), smd.getStoredScript("test"));
        assertEquals(1, smd.getStoredScripts().size());
    }

    @Override
    protected boolean enableWarningsCheck() {
        return true;
    }

    private ScriptMetadata randomScriptMetadata(XContentType sourceContentType, int minNumberScripts) throws IOException {
        ScriptMetadata.Builder builder = new ScriptMetadata.Builder(null);
        int numScripts = scaledRandomIntBetween(minNumberScripts, 32);
        for (int i = 0; i < numScripts; i++) {
            XContentBuilder sourceBuilder = XContentBuilder.builder(sourceContentType.xContent());
            sourceBuilder.startObject()
                .field("script")
                .startObject()
                .field("lang", randomAlphaOfLength(4))
                .field("source", randomAlphaOfLength(10))
                .endObject()
                .endObject();
            builder.storeScript(
                randomAlphaOfLength(i + 1),
                StoredScriptSource.parse(BytesReference.bytes(sourceBuilder), sourceBuilder.contentType())
            );
        }
        return builder.build();
    }

    @Override
    protected ScriptMetadata createTestInstance() {
        try {
            return randomScriptMetadata(randomFrom(XContentType.values()), 0);
        } catch (IOException ioe) {
            throw new UncheckedIOException(ioe);
        }
    }

    @Override
    protected Writeable.Reader<ScriptMetadata> instanceReader() {
        return ScriptMetadata::new;
    }

    @Override
    protected ScriptMetadata mutateInstance(ScriptMetadata instance) throws IOException {
        // ScriptMetadata doesn't allow us to see the scripts inside it so
        // the best we can do here is create a new random instance and rely
        // on the fact that the new instance is very unlikely to be equal to
        // the old one
        return randomScriptMetadata(randomFrom(XContentType.values()), 1);
    }

    @Override
    protected ScriptMetadata doParseInstance(XContentParser parser) {
        try {
            return ScriptMetadata.fromXContent(parser);
        } catch (IOException ioe) {
            throw new UncheckedIOException(ioe);
        }
    }
}